Usually, such a static pressure sensor is part of an anemometric unit which is intended to measure air data and so determine values of parameters such as the altitude of the aircraft, its speed, etc., which are in particular used to pilot the aircraft.
It is known that such a static pressure sensor normally comprises at least:                a probe provided with a pressure tap passing through the fuselage of the aircraft;        a module that is linked by a pipe to said probe; and        an activatable heating system which is provided to heat said probe.        
Any failure of such a static pressure sensor must of course be able to be detected quickly and reliably, since otherwise, the measurements taken will provide erroneous values for the abovementioned parameters (used for piloting), which can have very damaging consequences for the security of the aircraft when in flight.
It is known that human errors, in particular on airplane maintenance operations, can lead to the failure of such a static pressure sensor.
For example, the people responsible for washing the airplane often stick a piece of adhesive tape over the pressure tap of the probe, in order to prevent water from penetrating into the pipe linked to said probe during said washing. If the removal of the piece of adhesive tape after washing is forgotten, the pressure sensor will fail on the next flight of the aircraft, since it cannot measure the air pressure outside the fuselage. It will in fact measure the air pressure imprisoned in the pipe which is sealed (at its probe side end) by the piece of adhesive tape, this measured pressure obviously being different in flight from the outside pressure.
Various solutions are known (patent applications FR-2 847 669 and FR-2 857 447, for example) making it possible to detect the failure of a pressure sensor which is part of an anemometric unit of an aircraft. However, the known solutions only make it possible to detect a failure when the aircraft is flying. In the case of such a detection in flight, it is simply possible to stop taking into account during the rest of the flight the measurements taken by the failed pressure sensor, in order not to take account of false measurements (which is obviously important for safety), but repairing the failed pressure sensor is not possible. Although an anemometric unit of an aircraft normally comprises several pressure sensors so that the failure of one of said pressure sensors does not prevent the flight from continuing, the failure to take into account the data from a pressure sensor can, nevertheless, have a negative effect on the accuracy of the values of the parameters used to pilot the aircraft, which are derived from the measurements taken by this anemometric unit.